In the offshore segment of the petroleum industry one of the prevalent problems has been the connecting of an offshore platform or marine structure to a pipeline which normally carries petroleum products to an onshore storage area or from a well. Usually one or more well heads at the ocean floor are connected to a common line which conducts the products to a riser or conduit supported by the platform. The riser directs the crude liquid or gas product upwardly to a separation system at the platform's deck prior to the product being conducted away by another such pipeline, or shipped away by tanker.
As a matter of practice, the connection between the pipeline and the fluid conductor at the marine platform, is made by welding the pipe joint to the fluid conductor through the use of divers and/or highly technical equipment which is lowered to the sea floor. In the instance of relatively deep waters, the normal problem of making the above noted connection is substantially compounded. This results primarily from the hyperbaric atmosphere which limits the use of personnel and greatly increases the cost of such an operation.
Toward simplifying this laying of the desired pipeline the present invention provides a means whereby the lower end of the fluid carrying conductor or riser is adjustably connected to the platform. In the resting position the conductor is disposed in a substantially upright disposition so that its lower open end is adjacent to the ocean floor.
A provisional conductor which subsequently forms a portion of the pipeline, is detachably connected to the marine structure in a manner to permit pivotal movement of said provisional member in a substantially vertical plane. Pivotal movement will thus position the lower end of said provisional conductor in approximate alignment with the upright fluid conductor. Downward movement of the latter will then engage the respective members into a fluid tight connection between the pipeline and the conductor.
It is therefore an object of the invention to provide means for connecting a marine structure supported fluid conductor to a pipeline, without the necessity of operating underwater or utilizing divers. A further object is to provide an offshore platform including means for connecting a conductor or riser member to the pipeline through the use of a pivotally connected pipeline extension. A still further object is to provide an offshore structure of the type contemplated which simplifies the laying of a pipeline from the water's surface to the floor, after being initially connected to the structure's conductor lower end through a pivotal joint.